An air of unease set into the security circles on Sunday as they prepared for the disclosure of high-severity vulnerabilities in the Wi-Fi Protected Access II protocol that make it possible for attackers to eavesdrop Wi-Fi traffic passing between computers and access points.

The proof-of-concept exploit is called KRACK, short for Key Reinstallation Attacks. The research has been a closely guarded secret for weeks ahead of a coordinated disclosure that’s scheduled for 8am Monday, East Coast time. A website disclosing the vulnerability said it affects the core WPA2 protocol itself and is effective against devices running the Android, Linux, Apple, Windows, and OpenBSD operating systems, as well as MediaTek Linksys, and other types of devices. The site warned attackers can exploit it to decrypt a wealth of sensitive data that’s normally encrypted by the nearly ubiquitous Wi-Fi encryption protocol.